My GT mileage; over 204k. Turbo as no shaft play when checked at 174k.

My G\F's 05 WRX use same oil & OCI, but uses 1 single spin-on, Ea15k13 oil filter. The WRX as over 150k. I add 2-4qts over the 15k OCI. Turbo as no shaft play when checked at 150k.
Oil consummation hasn't change sense car was new.

My 07 Pontiac Solstice GXP, 2.0L DI turbo charge motor, Same oil & OCI, but No Ea filter is available. I use a WIX filter. Change oil filter only every 5k. GXP as over 86k. No oil consummation over it's 15k OCI. Amsoil know as a EA oil filter, just waiting to use up my WIX oil filters.

In short, check you oil level often & top as needed. Use oil & filter that will protect for the OCI your running. OA's is the only way you know that your oil & filter is up for the challenge. After that IMO no OA's are needed.This is what I have told others. That wanted or thinking about running Extends Drain Intervals.

If your not going to run Extends Drain Intervals. (IMO at least 7.5k) Them IMO you can use cheaper oil & filter to protect up to Subaru's 3750 OCI. What you do is up to you, at your own risk. If you do Extends Drain Intervals (at least 7.5k)I would do your OA's at your current OCI. Up to you plan on changing you oil & filter. For the 1st oil change. After you AO's come back "Good for Continuous Use" up to whatever OCI you decide, under 15K. Then all you have to do is to watch for oil usage. Remember that Amsoil only Recommends extended drain intervals with their oils. If use with their EA oil filters one is available.

Mike

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